Goes without saying that LAPD homicide detectives quickly got involved, and "are treating the case as a possible homicide." Oh, and they're "looking for other body parts in the area," officials tell the Times.

In the couple hours since the gruesome discovery of the head, the homicide investigation has reportedly spread into surrounding Bronson Canyon Park, and residents are Tweeting about a swarm of helicopters overhead. [Update: "It's ghetto bird mania outside!" says Hills dweller Aimee Allen.]

Speaking of residents: They were awfully mad at all those tourists tromping through their neighborhood to get an up-close view of the Hollywood sign. Just saying.

We've contacted the LAPD for updates on the investigation. But for the record, the human head (shudder) was discovered right near Camp Hollywoodland, in the 3200 block of Canyon Drive:

Update No. 1: Other news outlets are saying that two hikers, not a park ranger, first stumbled across the head. If so, our condolences. Via Reuters:

Two unidentified witnesses found the head in the Hollywood Hills near the Griffith Observatory, a popular hiking area. Homicide detectives were looking for further evidence in the area, including a search for a body, police said.

"Witnesses in the area found the head in a bag and called police," Los Angeles Police Department spokeswoman Karen Rayner said.

Update No. 2: OK, looking like the head was definitely discovered by two hikers and their dog. In fact, it "rolled out" of its bag when the dog tried to investigate, the Los Angeles Times reports in a followup post. As if the severed-human-head scenario could get any creepier.

The murder victim (and this is definitely believed to be a murder, at this point -- a murder worthy of the LAPD's Robbery-Homicide Division) has "salt-and-pepper hair" and is being delivered to the L.A. County Coroner's Office for dental identification, mysterious police sources tell the Times.

Great. Going to go crawl in bed and never wake up now, thanks.

Update No. 3: KNX news radio is reporting that cadaver dogs discovered a severed hand in the same vicinity this morning -- about 50 yards from the severed head. It was not in a bag.

Craig Harvey at the L.A. County Coroner's Office says he cannot yet confirm this, as there's no cell reception in the search zone, so he hasn't spoken with investigators.

But KTLA has similar report, and LAPD Commander Andy Smith tells the station that cops "believe at this point the head was dumped by somebody there, and very recently."

More on those poor hikers who made the big find:

The women had about nine dogs between them, and two of the dogs started playing with an object they found in a plastic bag, according to a statement from Los Angeles police.

The dog walkers took a closer look and realized the object in the bag was a human head.

Update No. 5: Annnnd the other hand drops. ``We've got to see if we can get any prints from the hand,'' the coroner tells City News Service. "If we get any prints, then the LAPD can go knocking on doors.''

Update No. 6: Now for the feet. According to a KNX reporter, they've been "found near the two hands and severed head in Bronson Canyon Park. All parts believed to be from same body."